Combining harvested waste CO2 and renewably-generated electricity, Audi takes the first step to producing the world's first carbon-neutral fuel.

Audi's e-fuels project won't fundamentally change how the company builds its cars. It won't drastically reduce trips to the pump. Nor will it introduce a radically new fuel to the industry. And yet, with its synthetically-produced e-gas, e-diesel, and e-methane, the German automaker hopes to use excess CO2 in the process of creating fuels, producing a gas that gives off just as much carbon as is used to create it.

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Today, Audi took the first major step in this ambitious project with the opening of power-to-gas facility in Wertle, Germany. This industrial-sized e-gas plant takes excess carbon dioxide harvested from landfills and biogas plants and combines it with hydrogen electrolyzed from water (using power generated from windmills or solar panels) to create a synthetic, carbon-neutral compressed natural gas that Audi claims is "virtually identical" to the stuff made from eons of decaying organic matter.

While any CNG-powered car could run on e-gas, the only way to purchase Audi's e-gas (somewhat) directly is to buy a 2014 Audi A3 Sportback g-tronand then order a quantity of the carbon-neutral fuel. Even then, those drivers will still be filling up at traditional CNG stations—only Audi will handle the payment and billing through an e-gas refueling card. In other words, drivers can subsidize, but not directly buy from, Audi's e-fuels program. (Think of it as a carbon offset program.)

Overall, Audi says, the e-gas plant could keep up to 2800 metric tons of CO2 out of the environment over the course of a year. In the grand scheme of climate change, that's not much. And because Audi's e-fuels project—which also includes an e-ethanol and e-diesel research facility in Hobbs, N. M.—is only carbon footprint reduction (albeit clever); their efforts, unfortunately, aren't cumulative. Until they can expand their e-fuel production capacity, the program's contribution to Audi's net CO2 reduction will stay locked at 2800 metric tons.

Cost for such fuels have yet to be announced. As with any fossil fuel alternative, price will almost certainly dictate success or failure. If Audi can keep e-fuel pricing on level terms with traditional fuel sources, then they have a chance at offering drivers yet another means to cut carbon emissions. However, whether or not Audi can sell consumers on complex carbon footprint reduction remains to be seen.